Tomato (Solanum lycopersicum L): Lycopene

                                             Tomato (Solanum lycopersicum L): Lycopene

Prof Yamini Bhusan Tripathi, PhD Biochemistry

Former Dean, Ayurveda Faculty, Institute of Medical Sciences, Banaras Hindu University,

CEO, Yamini Innovations (LLP), Varanasi-221005,yamini30@gmail.com, www.yaminiinnovations.com

Tomato (Solanum lycopersicum L. or Lycopersicon esculentum Mill) is used as vegetable and its quality depends on its dry matter, organic acids (ascorbic acid), minerals, vitamin C, A and E), sugars, essential amino acids (leucine, threonine, valine, histidine, lysine, arginine), monounsaturated fatty acids (linoleic and linolenic acids), potassium, folate, and non-nutritive phytochemicals like carotenoids and other polyphenols. In nature, about 600 carotenoids are found, which may be (i) highly unsaturated hydrocarbons, and (ii) xanthophylls (lutein, β-cryptoxanthin, and zeaxanthin). The major carotenoids in tomato, includes lycopene, α-carotene, β-carotene, γ-carotene, δ-carotene, phytoene, phyto-fluene, neurosporene, and lutein. Its major polyphenols include phenolic acids, caffeic acid, chlorogenic acid, hydroxycinnamic acid, homovanillic acid, sinapic acid, p-coumaric acid and ferulic acids). phytosterols (β-sitosterol, campesterol and stigmasterol). It has several flavonoids, flavanones, flavones, chlorophylls and anthocyanins. The Quercetin, kaempferol, myricetin, rutin (quercetin-3-O-rutinoside), naringenin chalcone, neoxanthin, lutein, α-cryptoxanthin and naringenin are the common flavonoids. It also has some glycoalkaloids like tomatine, which is a mixture of α-tomatine and dehydr-oxytomatine, which is toxic and gives protection to plants, against the pathogenic attack.  The flavonoid gets accumulated during maturation in tomatoes.

The Lycopene (C₄₀H₅₆), is the major constituent of tomato. It is an acyclic open chain hydrocarbon, known as a non-pro-vitamin-A carotenoid. It is an open chain, tetraterpene compound, consisting of eight isoprene units, 11 conjugated and 2 unconjugated double bonds. It is synthesized during ripening and responsible for its deep-red colour of tomato. Naturally it is found in “all the trans” isomer form, which has higher antioxidant capacity, but poor water-solubility and bio-accessibility. Only 10–30% of the dietary-lycopene is absorbed in GIT, but absorption get improved, when combined with oil/fat.  During processing, it gets converted to “cis isomer”, which attributes to its better absorption in the GIT. However, after absorption, it again gets reconverted to “trans” isomer, in the enterocytes, liver and stomach (Antioxidants 2020; 9, 706). After ingestion, it is transported to the liver as chylomicrons and further stored in testes, prostate, adrenal glands and liver, brain and skin. The bioavailability of Lycopene decreases with ageing. The half-life of Lycopene in human plasma is of about 2 to 3 days. The tomatoes are the richest source of lycopene, (about 11.21 mg/100 g wet weight), but it is also found in watermelon, guava, pink grapefruit, rosehips, papaya, and apricot.

Cultivation: About 182.3 million tons of tomato-fruits are grown annually, on 4.85 million hectares land, in the whole World (FAOSTAT, 2019). The Asian-countries, account for 61.1 % of world production with different varieties like Coeurde pigeon, Bella rosa, Deberao, Orange banana tomato, Yellow Beijing. The Cherry tomatoes ranked the highest in lycopene content. Tomato is planted in late spring or early summer and it can be harvested about 42 to 110 days from germination. The soil should be loamy, and well-drained with eight hours of full Sun/day exposure. Spacing among plants should be between 75x60 cm. Support tomato plants with stakes or cages once they're ten to 12 inches tall. Pinch it or bend the sucker back and forth gently is called simple pruning.

Processing: The Lycopene is vulnerable to heat, light, and pH changes, so its extraction and processing like bleaching, retorting, and freezing processes are done in the inert atmosphere to avoid its degradation. The Super Critical Fluid Extraction (SCFE), liquid extraction, saponification and boiling for 1 hour in the presence of 1% corn oil, increases its bioavailability. Frozen foods and heat-sterilized foods enhances storage shelf life. The raw tomatoes show the highest lycopene content (Bella rosa 10.44 mg/ kg fresh wt). It processed products includes 5-minute boiling, Peel removal, Smashing, Sauce, Tomato puree, Tomato ketchup. Among these the sauce showed least amount of lycopene (0.137 mg/kg fresh wt, the ketchup shows about 1.23 mg/kg fresh wt). 

Ayurvedic description:  All kinds of foods are having 6 rasas, with predominance of one Rasa, attributing to health benefits to the human, depending on their genetic constitution. The tomato has predominance of amla Rasa (sour Taste); Ruksha, laghu and Snigdha (Oily) in guna; with cooling Virya (Potency). So, it is beneficial for individuals having excess heat or Pitta-dosha imbalance. It is considered as “tridosh shamak” because of its laghu and ruksha guna, it can balance the increased Vata and Kapha also. The sour taste can potentially aggravate Pitta, or heartburn in some people, having Pitta as genetic constitution.  

Medicinal values: The lycopene is a functional-foods, which is defined as the dietary ingredients, affecting the host in a targeted manner to justify certain health claims, beyond its basic nutrition value. Its recommended intake as food is about 1.1 to 3.7 mg/day. Lycopene is a potent antioxidant, attributing to its potential for quenching of singlet oxygen (¹O₂). It downregulates the genes, involved in ROS generation in the cell. The antioxidant capacity is added by presence of other lipophilic (carotenoids and vitamin E) and hydrophilic (vitamin C and phenolic compounds) metabolites. It is effective in management of diabetes, healthy gut microbiome, skin health, atopic dermatitis, inflammatory disorders, oxidative stress-mediated malfunctions, metabolic syndromes, neurodegenerative diseases, obesity, hyperlipidemia, cardiovascular disorders, bone diseases, neural and reproductive disorders, immune response, exercise recovery, cancer, hepatic diseases. They help in visual disorders, because carotenoids are the precursors for the visual pigment rhodopsin. The lutein and zeaxanthin protect the retina from excess light and ultraviolet damage. The lycopene is the leading carotenoid in plasma and tissues, but its absorption gets reduced with aging. Lycopene is very effective in management of CVDs and to improve the ventricular remodelling, vascular and endothelial function and to reduce the atherosclerotic plaque size, and arterial stiffness. It is a natural neuroprotective agent and contributes to cognitive longevity and the treatment of cerebral ischemia, Parkinson’s disease (PD), Alzheimer’s disease (AD), subarachnoid haemorrhage, epilepsy, Huntington’s disease, and depression. It is also effective in different skin diseases, oral and dental diseases. Its anticancer properties are attributed to lycopine and other factors like fibre, vitamin C, and phenolic constituents. It modulates the cellular pathways that lead to cancer like anti-angiogenic properties, reduction in insulin-like growth factor (IGF) in blood, inhibition of macrophage migration, cyclooxygenase-2, NFkB (nuclear factor-κB), TNF-α (tumor necrosis factor alpha), iNOS (inducible nitric oxide synthase), PKB (protein kinase B), and CXC chemokines. It inhibits the Wnt/β-catenin signalling pathway, which is upregulated by inflammation and oxidative stress, leading to a variety of cancers. It inhibits the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, mediated increase in angiogenesis. When taken in excess, may cause nausea, vomiting, diarrhoea, indigestion, gas, and bloating and immunosuppression after long use. The wastes, obtained after tomato processing industry (i.e., the peels and seed extracts) are also of high use, as they are rich in oils and proteins.

(https://orcid.org/0000-0002-8093-1109)